Better by Design: Worm gear workhorse

Worm gearboxes are the workhorses of modern manufacturing, increasing motor torque and acting as speed reducers in myriad industrial applications. Their Achilles' heel — inefficiency — is also their strength, as worm gear designs can hold even the heaviest loads without slipping. Even so, the inherent sliding friction of worm drives allows efficiency of only 45% to 85%, depending on the gear ratio and application. To address this issue and increase gear-reducer efficiency, several European designers incorporate helical-bevel gearing, which significantly reduces sliding action, translating to higher efficiency and less wasted energy. However, these designs often don't work with standard C-face motors.

As another option, Grove Gear, Union Grove, Wis., built the IronMan E Series gear reducer — a design that marries the footprint of a traditional worm gearbox to the high efficiency and extra torque of helical-bevel gearing arrangements. To illustrate: A typical worm gearbox with a 2.4-in. center distance provides 1,000 to 1,200 in.-lb of torque, whereas the E Series offers 2,600 in.-lb in the same-size package. This additional torque is especially useful in applications requiring overload capacity, such as conveyors that require frequent starts, stops, and reversing. What's more, the E Series boasts an operating efficiency of 90% across all ratios. Materials are also engineered for power density: The E Series' modified helical-bevel steel gearing offers higher torque capacity and better wear resistance than traditional bronze worm gearing.

VITAL STATS

On display: Grove Gear IronMan E Series gear reducer

Key features: Will replace up to 6-in. center distance; four models available with double reduction ratios from 7.8:1 to 60:1; triple reduction units possible by adding a ratio multiplier; power to 8.5 hp

What it means to you: Higher efficiency and greater torque than traditional worm gearboxes in the same size footprint facilitate motor downsizing and reduced energy costs.